The research at Miles College provided for by the MBS grant deals with the effects of hormones on the radiation sensitivity of mice. It has been established that certain hormones will enhance survival of animals which have been exposed to ionizing radiation. The problem of the specificity of this effect has not been researched. Thus, it is necessary to determine if this effect is specific for a given cell such that tumor cells will not be affected by the hormone in this manner. It is also necessary to determine the effects of hormones on radiomimetic drugs. If similar effects are observed, combined radiomimetic drugs and hormones may be used in tumor therapy depending upon the specificity of this effect.